Selector-switch.



H. G. DIETL.

SELEQTOR SWITCH.

APPLICATION FILED 11211.11, 1913.

1,126,727. Patented Feb. 2, 1915.

2 SHEETS-SHEET 1.

Fl O? 25 24 7 /5 m /4 /6 I go O 22 0 THE NORRIS PETERS co. PHOTO-L!THO.. WASHING m". D. L

H. G. DIETL.

SELECTOR SWITCH.

APPLICATION FILED APR.11. 1913.

1,126,727, Patented Feb. 2, 1915.

2 SHEETS-SHEET 2 w 2677'; Huber) Goff/ieb Die/K THE NORRIS PETERS CO PHOTO LITHD-, WASHINGI'ON. D C.

PATENT OFFICE.

HUBERT- GOTTLIEB- DIETL, OF VIENNA, AUSTRTA-HUN GARY, ASSIGNOR T0 WESTERN ELECTRIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF ILLINOIS.

SELECTOR-SWITCH.

Application filedApril 11, 1913.

lector-Switches, ofwhich-the following is a full, clear, concise, and exact description.

This invention relates to. automatic switching mechanism, such as used in telephony, and more particularly to the type; of switch known as a line switch or selector, that is, a switch associated with a subscribers line which upon the initiation of aca'll' automatically selects and makes connection to an idle connecting-circuitortrunk line electromagnetically operated step-by-step mechanism for rotating it, three sets of movable terminalsinsulatively mounted upon 1 the shaft, and a bank of three stationary ter minal rows adapted for cooperation with said movable terminals; Each-ofthesets of movable terminals comprises three brushes and each brush consistsoftwo Wipers. The

corresponding wipersof the three sets are formed from disk-like members, each of which is cut away to. provide three equiani. gularly spaced. arms, at the ends of whlch are the wiper contacts. Thei'wipersiof one disk of each pair of disksarearranged to overlie those of the other so it willbe seen that each set of brushes will consist ofthree The wipers of each brush are arranged to engage on opposite sides of the stationary terminals pairs of radially extending wipers;

of the row individual thereto.- The stationary terminal bank consists of three arcuate rows of terminals, each row of which has an arcuate plate at each end thereof and, as shown in the present embodiment, twelve terminals therebetween. However, it is ob vious that the number of terminals maybe increased or diminished as desired. The arcuate plates of each terminal row are electrically united toone another. The curved plates of two of said rows are connected to- Specification of Letters Patent.

Patented Feb. 2, 1915.

Serial No. 760,445.

opposite sides of the calling line respectively. The arcuate plates of the third row of terminals are connected to a test conduotor. The contacts lying between said two arcuate platesrepresenttrunk or connecting circuit terminals and the contacts lying between the arcuate plates of the third row are test terminals. From an inspection of the drawing it; will readily be seen that of the three brushes having. access to the same row of stationary terminals, one will always be in. engagement with one or the other of the. arcuate plates, while one of the other brusheswill always be in a position to en-- gage atrunk terminal. Upon the initiation of a ea-ll at the substation connected to a switch, theshaft thereof will be automatically. rotated step-by-step until one of the sets of brushes engages'the terminals'ofv an idle trunkwhen such rotation will stop, thus connecting one of the arcuate plates in each row of terminals to a trunk terminal through the medium of, the rotatable three-armed brush members, one brush of each such member being at, this time in engagement with a trunk terminal and another brush being in engagement with: one or the other of the arcuate plates.

F01 a more complete disclosure of this in? vention, referenceisnow made to the drawings in whieh,- I

Figure 1 is aside elevation of the switching device; Fig. 2 illustrates the same viewed from below; Fig. 3- is a section on the line 33 of Fig. 1; Fig. 4: is a perspective view of a section of the terminal bank; and Fig. 5 is adiagrammatic illustration of the device and circuits with which it may be employed.

Referring. nowto the drawings, 1 represents a supporting platehaving at the lower edge thereof theoutwardly extending portion 2 terminating in theoutwardly and upwardly extending arms 3 to which is secured the plate 4: forming part of themounting for the electromagnet 5. Integral with the plated is an upwardly extending member Gwhich is angularly bent and continued in the horizontally extending member 7, which in turn is bent downwardly and continues as the member 8 rigidly secured to plate t, as shown at 9, thus forming a framework for the electromagnet' 5 and also. providing a bearing 10 for the upper end of the shaft 11. Another bearing for the shaft 11 is formed in the plate 4:. Downward movement of said shaft is prevented by a sleeve 12 which engages at one end the plate 4 and at the other end the ratchet wheel 13 fixed to the shaft 11 adjacent to the horizontal plate member 7. Secured to the lug 14 formed near the top of plate 6 is a spring holding pawl 15. Between the plate 4 and the upper horizontally extending member 7 is secured the armature 16 of the electromagnet 5. This armature is pivotally mounted between the points of the screws 17 and is normally held in its retracted position by the enga ement of a leaf spring 18 secured to the angularly extending lower end 19 thereof. An adjusting screw 20 is carried by a screw threaded block 21 fixed to the lower surface of the supporting plate 1. This screw passes loosely through the end of the spring 18 and has thereon a threaded washer 22 against which the spring rests; thus by rotating the screw in the threaded block 21 carried by the plate 4, or by rotating the washer on the screw, the distance of the end of the spring 18 from the plate 1 may be altered to adjust the retractile force exerted on the armature 16. Carried by the lug 28 integral with the upper end of the armature 16 is a ratchet spring 24 which engages the teeth of the ratchet wheel 13 and whereby the shaft 11 may be rotated upon attraction of the armature 16 by the electromagnet To prevent the shaft from taking more than one step upon the attraction of the armature 16 a screw 25 is provided which is adapted to engage the beveled end of the spring 24, thus positively stopping the rotation of the shaft at the end of each step.

. tigidly secured to the lower side of the plate 2 is the cylindrical bank 26 of stationary terminals which comprises three rows of contacts. At each end of each row of contacts is an arcuate plate 28 of substantially 60 extent. Located between these plates 28 and in the same plane therewith is a series of twelve contacts 29 which repre sent the terminals of trunk lines. These trunk terminals occupy an arc of substantially 120. Thus, it will be seen that as the brush arms are equally spaced about the shaft 11, some one of the brushes will always be in a position to engage a trunk terminal. Of the other brushes one will always be in engagement with one of the arcuate plates 28 as at the instant one brush leaves one plate 28 the next brush passes on to the other plate. The arcuate plates 28 and the terminals 29 are secured in position by being clamped between the plates of insulation 30 by the screws 31 and the upper and lower clamping plates 32, 33 respectively. Each of the terminals at the rear thereof is formed into a soldering terminal by curring each edge inwardly to form a recess 34 in which the wire may be secured by solder.

Insulatively secured to the shaft 11 are three sets of movable terminals or brushes so arranged as to operatively engage said rows of stationary terminals, respectively, upon rotation of said shaft. Each of these sets of movable terminals comprises three alined brushes and each brush consists of two wipers 36. The corresponding wipers of each of these three sets are formed as equiangularly spaced and radially extending arms 37 of the disk-like members 38, which are insulatively secured on the shaft 11 in pairs in any desired manner. Each of the arms 37 is provided at the outer end thereof with the laterally projecting portion slotted as shown at 40 to form a pair of wiping contacts 41. The corresponding wipers of the several disks are arranged in rows and the wipers of which each brush consists are spaced apart and their laterally extending portions 39 are curved toward each other and have their extreme edges in yielding engagement, thus forming a V-shaped restricted opening through which the stationary terminals may pass on the movement of the brushes by the rotation of the shaft. It will thus be seen that the pair of wipers of which each brush consists is arranged to engage on opposite sides of the stationary terminals in a row individual thereto. As each brush comprises two wipers and each wiper is provided with two wiping contacts, it will be seen that four contact surfaces are provided, one for each of the wiping contacts 41, thus assuring a good electrical contact of the brushes with the stationary contacts. The three electrically connected brushes which engage the same row of contacts will hereinafter be referred to as a movable terminal unit.

Referring now to Fig. 5 for the operation of the apparatus and of the circuits with which it is adapted to be used, A represents a subscribers telephone apparatus arranged to be connected with the switch illustrated through the sides of the line L and li and this switch automatically operates to extend the line to a connecting circuit T T t leading to a selector or a connector. The subscribers apparatus is of the usual construction with the exception that a grounded contact surface 43 is provided with which the switch hook is adapted to make momentary contact when the receiver is removed therefrom. Upon the removal of the receiver from its hook, circuit is completed from the live side of the grounded battery 44, wire 45, winding of line relay 40, wire 47, back contact 48, armature 49 of relay 50, side of the line L subscribers transmitter, switch hook and contact 43 to ground. This current impulse through the relay 46 causes it to pull up its armatures 51, 52, 5S providing a locking circuit for itself from the live pole of the grounded battery 44, wire 45 relay 46, wire 47, back contact 48 and armature 49 of relay 50, wire'54, armature 52 of relay 46, front contact 55 to ground, thus assuring that relay 46 remains energized until the locking circuit therefor is interrupted by the energization of relay 50. Upon the attraction of armature 51 of relay 46, circuitis completed from the live pole of the grounded battery 44, wires 56, 57, front contact 58, armature 51, wire 59, high resistance winding and low resistance winding 62 of test relay 61, wire 63 to the segmental contact 28 of the lowermost row of stationary terminals, through two of the brushes and arms 37 of the movable terminals individual to this row, contact 29, test conductor 25 of the connecting circuit, high resistance R, armature 64, back contact 65 of relay 66 to ground at 67. If the trunk line terminating in the contacts on which the brushes now rest is idle, relay 61 will pull up, providing a locking circuit for itself from battery 44, wire 56, armature 68 and front contact 69 of relay 61, low resistance winding 62 and to ground as before described. The attraction of armature 68 of relay 61 also completes a circuit from battery 44, wire 56, armature 68 and front contact 70, wire 71, relay 50 to ground, whereupon said relay attracts its armatures 72, 49 and 73. The attraction of the armatures 72 and 49 completed a circuit from the calling subscriber to the side T and T of the trunk line as follows: substation A, line L armature 72, front contact 74 of .relay 50, wire 75, segmental contacts 28 of the uppermost row of stationary contacts, two of the brushes and arms 37 of the uppermost movable terminal unit, contact 29 to trunk strand T and from substation A through line L armature 49 and front contact 76 of relay 50, wire 77, segmental contacts 28 of the middle row of stationary contacts through the brushes and arms of the intermediate movable terminal unit, contact 29 to the side of the trunk line T thus connecting the calling subscriber to an idle connecting circuit. The branches Z and Z of the sides L and L respectively of the subscribers line lead to multiple contacts of the connectors through which subscriber A may be reached when called, and the strand t leads to the multiple test contacts of said connectors. The energization of relay 50 has also drawn the armature 73 into engagement with its contact 78, thus placing ground on the multiplied test contacts of the connector switches through the conductor t to insure the privacy of the connection. If, however, one of the brushes of the lowermost brush unit engages a multiplied contact of a busy trunk, the relay 61 will not be energized as the'high resistance of its windings 60 and 62 will be shunted by the low resistance winding; 62 of the test relay of the line now associated with the trunk through a circuit the same as the previously described locking circuit for the test or cutoff relay 61. That is, from the live side of the grounded battery 44 to the switch now connected with the trunk line, through the wire 56, armature 68, contact 69, winding 62, wire 63, segmental contact 28, two of the brushes and arms of the lowermost movable brush unit to contact 29 of said busy switch and then through the multiplied connections to contact 29 of the line switch of subscriber A. As the resistance R is relatively high as compared to the resistance of the holding coil 62of relay 61, the battery potential across the terminals of the series coils of the cutoff relay 61 of the calling subscriber will be insufficient to allow the pulling up of this relay, as both of its coils will at this time be in series. In the case previously assumed, that is, that 'the trunk lines to which one of the brushes of the switch was connected is idle, the circuit for the stepping magnet 5 completed at armature 58 and front contact 79 of relay 46 was immediately interrupted at the back contact 80 of relay 61 by the attraction of its armature 68. However, if the trunk SDI line with whose terminals the switch is now in engagement is busy, the relay 61 will not be energized for the reasons previously described, and the circuit for the stepping magnet 5 will not be interrupted by the pulling up of armature 68. The circuit for the, stepping magnet 5 is as follows: from live pole of the grounded battery 44, wire 56, armature 68, back contact 80, wire 81, contact 79, armature 58 wire 82, coil of the stepping magnet 5, interrupter 83 to ground; thus providing current for the stepping magnet and rotating the shaft 11 of the switch to position the brushes thereof upon successive contact terminals of trunk lines. As soon, however, as the lowermost brush of the switch engages a contact 29 in which an idle trunk terminates, the coils of relay 61 will not be shunted at some other switch and said relay will be energized through a circuit including its windings 60 and 62 in series, as previously described, thus interrupting the circuit for the stepping magnet 5 and stopping the brushes in engagement with the contacts of the first idle trunk. Relay 61, in pulling up, closed a locking circuit through the low resistance winding 62, as before described, to place test potential on the multiplied terminals of the trunk with which the switch is now in engagement. The attraction of the armature 68 also completed a circuit for the relay 50, which in pulling up connected the calling substation to the trunk line, as previously described. Upon disconnection the subscriber hangs his receiver upon the hook, thus effecting changes atthe selector or conmotor to which the trunk extends, which changes act to complete an energizing circuit for the coil 66 which attracts its armature 6% to interrupt the holding circuit for the relay 61. Armature 68 now falls back interrupting at '70 the circuit for the relay 50 to disconnect the calling line from the switching apparatus, and returning the several relays to their normal inactive position. It may be noted, however, that the switch brushes have no normal position and will remain in the position last used until another call is initiated at the substation associated therewith.

I claim 1. In a telephone exchange, a switch, a row of contacts thereat comprising line terminal contact plates and a plurality of other line terminals, a support, a plurality of electrically connected brushes on said support arranged for engagementwith said row of contacts, and means for moving said support whereby one or the other of said contact plates may be electrically connected to one of said other line terminals through the medium of said brushes.

2. In a telephone exchange, a switch, electrically connected plates representing a line terminal thereat, a row of contact terminals of other lines, a support, a plurality of brushes thereon adapted to traverse said row of contacts and said plates, some one of said brushes being always in engagement with one or another of said plates, and one of said brushes being in a position for engagement with successive contact terminals.

3. In a telephone exchange, a switch, a row of contacts thereon comprising electrically connected contact plates representing a line terminal and a row of other line terminals, a support, a plurality of brushes on said support arranged for engagement with said row of contacts, some one of said brushes being at all times in engagement with one or another of said plates and another of said brushes being in a position to engage some one of the line terminals.

4. In a telephone exchange, a switch, a terminal bank of contact rows, each row comprising electrically connected terminal contact plates of a line and terminals of a plurality of other lines, a support, a plurality of electrically connected brushes on said support for engagement with each of said rows of contacts, one of each plurality of brushes being at all times in engagement with some one of said contact plates, an other of said brushes being adapted for successively engaging said other terminals, whereby said line may be electrically connected to one of said other lines through the medium of said brushes.

5. In a telephone exchange, a switch, a cylindrical terminal bank comprising a plurality of rows of contacts, each row comprising electrically united arcuate plates connected to a line and a row of terminals of other lines, a shaft, a plurality of brushes on said shaft, for engagement with each of said rows of contacts, some one of each plurality of brushes being at all times in engagement with one or another of said contact plates, another of said brushes being adapted for successively engaging said other terminals whereby said line may be electrically connected to one of said other lines through the medium of one of said brushes.

6. In a telephone exchange, a switch, a cylindrical terminal bank comprising a plurality of rows of contacts, each row consisting of a pair of electrically connected arcuate plates connected to a line and a plurality of other line terminals therebetwecn, a roatable shaft extending through said bank, brushes on said shaft, an electrically connected plurality of which is arranged for engagement with each row of contacts, said brushes being so spaced that some one of each plurality is always in engagement with one or the other of said pair of plates while another of said brushes is arranged for engagement with successive terminals of said other lines, and means for rotating said shaft whereby said line may be connected to one of said other lines through the medium of two of said brushes.

7. I11 a switch, circular rows of contacts, each comprising a pair of electrically united line terminals and other terminals therebetween, a shaft, a plurality of brushes thereon arranged to traverse each of said rows, the brushes which are adapted for engagement with the same row being electrically connected, and means for rotating said sha'lt whereby one or the other of said line terminals will at all times be electrically connected through the medium of said brushes to one of said other terminals.

8. In a switch, a circular row of contacts comprising a pair of electrically united line terminal plates and other terminals therebetween, a rotatable shaft, a disk mounted on said shaft, a plurality of radially extending arms integral with said disk, a wiper at the outer end of each or" said arms, the arms of said disk being so arranged that one wiper will always engage one or another of said line terminal plates and another wiper will always be in a position to engage some one of said other terminals.

9. In a switch, a circular row of contacts comprising a pair of electrically united plates connected to a line and a row of terminals of other lines therebetwcen, a shaft, a disk insulatively mounted on said shaft, three equally spaced radial arms integral with each of said disks, a wiper at the outer end of each of said arms, some one of said wipers being at all times in engagement with one or another of said plates, another of said Wipers being arranged for successively engaging terminals of other lines, and means for rotating said shaft Whereby'said line may be connected to one of said other lines through the medium of said Wipers.

10. In a switch, a circular row of contacts comprising a p air of electrically united plates connected to a line and a row of terminals of other lines, a rotatable shaft, a pair of disks insulatively mounted thereon, three equally spaced radially extending arms integral With each of said disks, a Wiper at the outer end of each of said arms, said arms being so arranged that their respective Wipers Will simultaneously engage opposite sides of said contacts, a pair of said Wipers being at all times in engagement with one or the other of said plates While another pair is arranged for successively engaging the terminals of other lines, and means for rotating said shaft whereby said line may be connected to one of said other lines through the medium of said Wipers.

11. In a switch, a cylindrical terminal bank comprising a plurality of roWs of contacts, each row consisting of a pair of electrically united arcuate plates connected to a line and a plurality of other line terminals therebetWeen, a shaft, a pair of disks insulatively mounted on said shaft for each contact row, three equally spaced radial arms integral With each of said disks, a Wiper at the outer end of each of said arms, the arms of each pair of disks being so arranged that the corresponding Wipers are adapted to simultaneously engage opposite sides of the terminals in their row, some one pair of said Wipers being at all times in engagement with one or the other of said arcuate plates and another of said pairs of Wipers being arranged for successively engaging said terminals of other lines whereby said line may be connected to one of said other lines through the medium of said Wipers.

In Witness whereof, I hereunto subscribe my name this 28 day of March A. D., 1913.

HUBERT GOTTLIEB DIETL. l/Vitnesses AUGUST FUGGER, ADA MARIA BERGER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

